The Brain Beneath The Waves
A pale, attenuated summer sunlight washed across the calm waters of Alaska's Inside Passage, and wind-ripples tickled the surface. We had anchored in a remote cove, protected from Pacific surge by barrier islands. Off the lee shore of Chichagof Island (watch out for the grizzlies!), a slender finger of land probed the swift, nutrient-rich current like a swizzle stick. Good conditions for localized upwelling, for whale food, and for finding hungry whales.
ALL IN THE FAMILY: Our small inflatable craft slowly approached a group of humpback whales. Alaska Whale Foundation researchers, working under federal permits, had been studying this group of whales, famous for their sophisticated bubble-net feeding, for years. The core group included "Captain Hook," "Blubberlips,” and several others. "Rake" - a new mom, had parked her nearly-weaned calf safely on the sidelines: the action would soon become intense. Cameras were poised, and I assisted a scientist in lowering a hydrophone. We watched and waited.
KNOWING THE SIGNALS: Everyone knew the drill: the whales surrounded a school of young Pacific herring. Each whale had taken up a pre-determined position at the surface. The plan was to surround them with a 3-D curtain of bubbles exhaled sub-surface to startle and compact them into dense "bait-balls." One whale dove: this was the net-blower, who would set things into motion. Having set the net deep below, he laid down a series of pulsed calls, and soon others dove, in turn, corralled the fish, and joined the chorus of voices. Finally, a trumpeting blare signaled a rush to the surface, whales’ huge mouths gaping, their pleated throats distended by volumes of fish and sea water. Success!
BREAKING BREAD TOGETHER: To achieve this level of sophisticated cooperative feeding, both visual and acoustic tools were employed. These whales evaluated, even while they hunted, constantly communicating vital information and adjusting strategies. Sometimes the net contained too few fish, and a lunge to the surface would waste valuable energy; abort mission.
SPINDLE-BRAIN: As a newbie to this study, I pondered, Who was quarterbacking? Do they switch roles? Is there a humpback vocabulary, an ethogram or catalogue of their behaviors? These acoustic recordings, combined with underwater and surface videography, would provide insights into whale communication over time, and perhaps help our species understand their conservation needs better. Like us, humpbacks possess spindle neurons in their brain’s cortex; few earthly creatures do, aside from highly intelligent mammals such as great apes, elephants, and some cetaceans (dolphins, porpoises, and whales). Neuroanatomists say spindle cells are what make us “human,” with functions like complex speech, self-recognition, the ability to anticipate problems, to strategize, form hunches, and have empathy for unrelated others. Found in the big brains of great apes and elephants, they are abundant in humans, too. But by comparison, spindle neurons are three times more abundant in some cetaceans than ourselves. This, plus these whales’ behaviors, seem to confirm their higher-level brain function. Humpbacks are famous for their complex songs. They develop and recognize their personally identifying signature songs (“Hey guys, it’s me!”), and modify them over time (“Still me, here!”). They are social networkers par excellence. Just like us.
Humpbacks are now feeding off our coast. If you see one, give a salute; it may be your equal, in some respects. And seeking out commonalities is a healthy way to approach how other beings exist and function, and how we live and coexist among them. Learn more at https://www.smithsonianmag.com/science-nature/brain-cells-for-socializing-133855450/ and at https://marinesanctuary.org/blog/bubble-net-feeding-what-is-it/
This November at the San Francisco Zoo, Greater Farallones National Marine Sanctuary will sponsor a soiree and talk examining humpback whale song and the Search for Extraterrestrial Intelligence (SETI). Featured is Dr. Laurance Doyle, who explores the relation of information theory to whale vocalizations, and searches for patterns in their communication systems as a proxy for an ETI signal, should one be received. Details will be posted at www.farallones.noaa.gov.
